A rugged High Capacity Air Vent designed to purge free air from liquid systems at operating pressure up to 150 psig. The Model 107A Air Vent has cast iron body and bonnet, with stainless steel, brass and EPDM internal components and is suitable for a maximum operating temperature of 250 deg F. The Air Vent has a 3/4 in NPT inlet and 3/8 in NPT outlet.